Couching or laid work is an embroidery technique dating back to 1070. It was one of two main techniques used in the Bayeux tapestry, a European historical work of art, consisting of fifty different scenes, and measuring 230 feet long. Laid work was also used traditionally on textiles in medieval England and Japan, with extensive use of metallic thread. Another location with a strong tradition for this intricate embellishment, was in Palestine, with production centred in Bethlehem. The Wikipedia definition is:
In embroidery, couching and laid work are techniques in which yarn or other materials are laid across the surface of the ground fabric and fastened in place with small stitches of the same or a different yarn.
Once you take a closer look at this type of embellishment, as shown in the last picture of the post, it is mind boggling to absorb; how much time and attention to detail, goes into this type of needle work.